For inspecting an electrical characteristic of an object to be inspected such as a wafer, an inspection device such as, for example, a probe device is used. The inspection device is provided with a probe card coming into electrical contact with the object to be inspected, and inspects electrical characteristics of IC chips formed on the object to be inspected by bringing a plurality of probes attached to the probe card into electrical contact with electrode pads of the IC chips.
However, since the electrode pads are formed of conductive metal such as, for example, aluminum, and oxide films formed on surfaces of the electrode pads serve as insulators, it is not possible to establish electrical continuity only by bringing the probes into contact with the electrode pads. Therefore, the electrical continuity between the probes and the electrode pads is established in such a manner that the probes scribe surfaces of the electrode pads to shave off the oxide films while given a predetermined contact load (stylus pressure), or the oxide films are pierced through by tips of the probes.
For example, a patent document 1 proposes a probe to pierce through an oxide film of an electrode pad. This probe has at tip portions thereof a plurality of projections, and owing to these projections, the probe has an increased contact area that comes into contact with the electrode pad, and the projections pierce through the oxide film, so that the probe comes into electrical contact with the electrode pad. As the projection, proposed are a lattice-formed projection with a tip thereof having an acute-angled triangular cross section, a spindle-shaped projection with a tip thereof having an acute-angled triangular cross section, and the like.
Further, a patent document 2 proposes a method of manufacturing a probe card in which irregularities are formed on a tip surface of a bump connected as an inspection electrode of a semiconductor chip. Moreover, a patent document 3 also proposes a contactor of the same type as that in the patent document 2 and a method of forming the contactor. The bumps proposed in these patent documents are also arts in which the irregularities on the tip surface of the bump break an oxide film of an electrode pad, as in the patent document 1.
[Patent document 1] Japanese Patent Application Laid-open No. Hei 11-051970
[Patent document 2] Japanese Patent Application Laid-open No. Hei 08-306749
[Patent document 3] Japanese Patent Application Laid-open No. Hei 10-132854